1. Technical Field
The field of the currently claimed embodiments of this invention relates to robotic systems, and more particularly to an active vibration damping device for use in cooperative control robotic systems and to cooperative control robotic systems that include an active vibration damping device.
2. Discussion of Related Art
Robots are often used during medical procedures, in some cases to reduce unwanted motion of the surgeon's hand due to physiological tremor. Many steady hand robots, such as those shown in FIG. 1, use a cooperative control method in which the robot and the user both hold a tool, and the robot moves according the force that the user exerts on the tool. The tool may attach to the robot using a quick release tool holder, which allows for easy exchange of different tools, and fast removal of a tool in the case of an emergency. In this configuration, different kinds of vibrations may appear at the extremity of the tool, either because of induced vibrations created by the robot's motors or because of shocks that could be produced during the surgical procedures. For example, the tool may bump into or suddenly lose contact with sample tissue, inducing vibrations. The tool is highly sensitive to vibrational forces due to its low stiffness and cantilever configuration.
Although significant research has been devoted to developing active vibration damping devices, the existing devices are either complex, active damping devices using linear actuators,1,2,3 or address only one-dimensional vibration damping of a rectangular cross section cantilever beam.4,5 